1. Field of the Invention
The present invention is directed to screen assemblies for shale shakers, mounting structure for such screen assemblies, shale shakers with such screen assemblies, and methods of using such mounting structures, screen assemblies and shakers.
2. Description of Related Art
Vibratory separators are used in a wide variety of industries to separate materials such as liquids from solids or solids from solids. Typically such separators have a basket or other screen holding or mounting apparatus mounted in or over a receiving receptacle or tank and vibrating apparatus for vibrating the basket. One or more screens is mounted in the basket. Material to be treated is introduced to the screen(s) either by flowing it directly onto the screen(s) or by flowing it into a container, tank, or xe2x80x9cpossum bellyxe2x80x9d from which it then flows to the screen(s). Also in some multi-screen apparatuses material flows from an upper screen onto a lower screen.
The prior art discloses a variety of mounting systems and apparatuses for releasably mounting a screen assembly to a shale shaker. These include drawbar and hookstrip apparatuses; inflatable device systems; wedge systems; e.g. the systems described in U.S. Pat. No. 6,179,128 issued Jan. 30, 2001; U.S. Pat. No. 5,392,925 issued Feb. 28, 1995; U.S. Pat. No. 4,882,054 issued Nov. 21, 1989; U.S. Pat. No. 4,582,597 issued Apr. 15, 1986; and in the prior art referred to in each of these references.
Referring now to FIG. 5, a prior art shale shaker 1 has a screen 2 (with screen or screening cloth or mesh as desired) mounted on vibratable screen mounting apparatus or xe2x80x9cbasketxe2x80x9d 3. The screen 2 may be any known screen or screens. The basket 3 is mounted on springs 4 (only two shown; two as shown are on the opposite side) which are supported from a frame 6. The basket 3 is vibrated by a motor 5 and interconnected vibrating apparatus 8 which is mounted on the basket 3 for vibrating the basket and the screens. Elevator apparatus 7 provides for raising and lowering of the basket end.
FIG. 6 discloses an example of a prior art shaker system (e.g. as shown in U.S. Pat. No. 5,190,645 incorporated fully herein for all purposes). The system A has a shale shaker K having a screen or screens S. The screen(s) S are mounted in a typical shaker basket B and one or more vibrators V (any known suitable shaker vibrator) vibrate the basket B and hence the screen(s) S. The other components of the system A are as described in U.S. Pat. No. 5,190,645.
There is a need, recognized by the present inventors, for an efficient and effective screen mounting structure and method for screen assemblies for shale shakers. There is a need, recognized by the present inventors, for an efficient and stable mounting of screens to a shale shaker.
The present invention discloses, in at least certain aspects, a screen assembly for a shale shaker, the screening assembly with one, two, three, four or more pins, studs, or fingers projecting downwardly from a lower support, the pins, studs, members, or fingers (xe2x80x9cprojecting membersxe2x80x9d) for insertion into a corresponding holes in a shale shaker screen assembly mounting tray, bed, or deck. Such pin(s), stud(s), and/or finger(s) provide for correct emplacement and positioning of the screen assembly (or assemblies) on the shale shaker tray, bed, or deck and also stabilize the screen assembly or assemblies during operation of the shale shaker. The downwardly projecting member(s) may be formed integrally of a screen support (frame, strip support, perforated plate, unibody structure) and/or they may be releasably attached to or connected to the support.
A shale shaker, in one embodiment according to the present invention (e.g. with basic components as the prior art shakers described or referred to herein) is, according to the present invention, provided with one or more screen assemblies with such projecting members as described herein according to the present invention. Such a shaker has a hole or holes in its screen-mounting tray, bed or deck corresponding to the pin(s) and/or finger(s) of the screen assembly (or assemblies) mounted thereon.
A screen assembly according to the present invention may be any known shale shaker screen or screen assembly to which the pin(s), stud(s), and/or finger(s) are added.
The present invention, in one embodiment includes a shale shaker with a frame; a xe2x80x9cbasketxe2x80x9d or screen mounting apparatus in the frame with a bed, tray or deck for a screen assembly or screen assemblies therein; pin(s) and/or finger(s) projecting up from the bed, tray or deck; one or more screen assemblies according to the present invention with a hole (or holes) corresponding to the pin(s) and/or finger(s) of the deck, bed or tray; the one or more screen assemblies mounted to the basket with the pin (s0 and/or finger(s) projecting into the corresponding hole or holes of the screen assembly or screen assemblies according to the present invention; basket vibrating apparatus; and a collection tank or receptacle below the basket. In one particular aspect such a shale shaker treats drilling fluid with drilled cuttings, debris, etc. entrained therein. With such a shale shaker, the pin(s) and/or finger(s) of the deck, bed or tray can be formed integrally of the deck, bed or tray; or the pin(s) and/or finger(s) may be part of strips, bars, wear strips or elongated members that are releasably connectable to the deck, bed or tray. In one particular aspect, such pin (s0 and/or finger(s) are on separate wear strips that are releasably connected to a shaker tray and which, in position thereon, provide an upward force that forces a screen assembly thereabove upwardly, facilitating the maintenance in position of the screen assembly. Wear strips that are made in an originally upwardly bowed configuration can provide such an upward force or an initially flat wear strip that is installed so that it bows slightly upwardly can provide such a force.
In other aspects of the present invention a hole or holes is or are provided in the upper surface of a support of a screen assembly (or in the lower surface of the support), e.g., but not limited to in part of a tubular frame of a screen assembly and a projecting member or members are moved into such hole or holes (e.g., a downwardly projecting member on a screen assembly holding member or structure or on an air bladder that is inflated above a screen assembly to secure it in place on a shaker deck, bed or tray or an upwardly projecting member on a screen assembly holding member or structure or on an air bladder that is inflated below a screen assembly to secure it in place on a shaker deck, bed or tray). In certain such aspects the screen assemblies shown in the drawings and described in detail below have the hole or holes in the topmost surface of a screen frame or tubular support rather than in the bottom thereof.
It is, therefore, an object of at least certain preferred embodiments of the present invention to provide:
New, useful, unique, efficient, non-obvious screen assemblies for shale shakers and methods for using them to separate components of material to be treated thereby;
Such screen assemblies, and shale shakers therewith, with one or more downwardly projecting members (e.g., studs, positioning pins or fingers) for releasably positioning and mounting such a screen assembly on a shale shaker mounting structure (bed, tray deck); and
New, useful, unique, efficient, non-obvious shale shakers with one or more upwardly projecting members on the shaker""s deck, bed or tray for insertion into corresponding hole(s) on a screen assembly support of a screen assembly to be mounted on the shaker.
New, useful, unique, efficient, non-obvious screen assemblies with a plurality of glued-together layers (e.g., one two, three or more) of screening material with at least one hole through the layers and through a plate on one side of the combination of layers of screening material, and, in one aspect, such a plate on both sides of the combination of glued-together layers of screening material; and in one aspect such a combination of glued-together layers of screening material with a hook apparatus on one side or end thereof for selective tensioning in a shale shaker; and in one aspect such a screen assembly with one or more projecting members projecting from a plate on the top of or from a plate on the bottom of the screen assembly;
New, useful, unique, efficient, non-obvious wear strips for for screen assembly mounting structures of shale shakers and methods for using them.
The present invention recognizes and addresses the previously-mentioned problems and long-felt needs and provides a solution to those problems and a satisfactory meeting of those needs in its various possible embodiments and equivalents thereof. To one of skill in this art who has the benefits of this invention""s realizations, teachings, disclosures, and suggestions, other purposes and advantages will be appreciated from the following description of preferred embodiments, given for the purpose of disclosure, when taken in conjunction with the accompanying drawings. The detail in these descriptions is not intended to thwart this patent""s object to claim this invention no matter how others may later disguise it by variations in form or additions of further improvements.